LT1 issues -- Opti? Limp-home mode?
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LT1 issues -- Opti? Limp-home mode?
I did one run on an autox course this week -- hitting the rev limiter in second on one or two stretches. Near the end of the run the car shut down.
Subsequently, it would start and idle, until I turned on the AC, then it would die. There was a bit of a squealing sound, but all of the pulleys on the accessories turned with no issue with no load. Oil pressure was fine, temperature was fine, and there was no leaks or anything else.
When running without the AC, the car really struggled to rev beyond 3000 RPM. The squeal was intermittent, and then went away. I didn't hear any knocking or rattling.
Earlier in the day, the car had some trouble starting -- I'd turn the key and there would be no cranking at all. This happened twice, and then it went away and I didn't have any more problems.
I wonder if I have opti-spark issues -- I've been searching, and it seems that there are many symptoms of a bad opti-spark. I also wonder if the ECM has acted up.
If I had over-revved the engine, and spun a rod, I shouldn't have good oil pressure.
If I had over-revved the engine, and had valves collide with pistons, the car shouldn't run.
Any other thoughts? The car's at a trusted garage, but I'm curious to what others think.
Worst case -- time for a modded motor.
Rob
Subsequently, it would start and idle, until I turned on the AC, then it would die. There was a bit of a squealing sound, but all of the pulleys on the accessories turned with no issue with no load. Oil pressure was fine, temperature was fine, and there was no leaks or anything else.
When running without the AC, the car really struggled to rev beyond 3000 RPM. The squeal was intermittent, and then went away. I didn't hear any knocking or rattling.
Earlier in the day, the car had some trouble starting -- I'd turn the key and there would be no cranking at all. This happened twice, and then it went away and I didn't have any more problems.
I wonder if I have opti-spark issues -- I've been searching, and it seems that there are many symptoms of a bad opti-spark. I also wonder if the ECM has acted up.
If I had over-revved the engine, and spun a rod, I shouldn't have good oil pressure.
If I had over-revved the engine, and had valves collide with pistons, the car shouldn't run.
Any other thoughts? The car's at a trusted garage, but I'm curious to what others think.
Worst case -- time for a modded motor.
Rob
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Joined: Jan 2005
Posts: 10,641
Likes: 13
From: Slidell Louisiana
I did one run on an autox course this week -- hitting the rev limiter in second on one or two stretches. Near the end of the run the car shut down.
Subsequently, it would start and idle, until I turned on the AC, then it would die. There was a bit of a squealing sound, but all of the pulleys on the accessories turned with no issue with no load. Oil pressure was fine, temperature was fine, and there was no leaks or anything else.
When running without the AC, the car really struggled to rev beyond 3000 RPM. The squeal was intermittent, and then went away. I didn't hear any knocking or rattling.
Earlier in the day, the car had some trouble starting -- I'd turn the key and there would be no cranking at all. This happened twice, and then it went away and I didn't have any more problems.
I wonder if I have opti-spark issues -- I've been searching, and it seems that there are many symptoms of a bad opti-spark. I also wonder if the ECM has acted up.
If I had over-revved the engine, and spun a rod, I shouldn't have good oil pressure.
If I had over-revved the engine, and had valves collide with pistons, the car shouldn't run.
Any other thoughts? The car's at a trusted garage, but I'm curious to what others think.
Worst case -- time for a modded motor.
Rob
Subsequently, it would start and idle, until I turned on the AC, then it would die. There was a bit of a squealing sound, but all of the pulleys on the accessories turned with no issue with no load. Oil pressure was fine, temperature was fine, and there was no leaks or anything else.
When running without the AC, the car really struggled to rev beyond 3000 RPM. The squeal was intermittent, and then went away. I didn't hear any knocking or rattling.
Earlier in the day, the car had some trouble starting -- I'd turn the key and there would be no cranking at all. This happened twice, and then it went away and I didn't have any more problems.
I wonder if I have opti-spark issues -- I've been searching, and it seems that there are many symptoms of a bad opti-spark. I also wonder if the ECM has acted up.
If I had over-revved the engine, and spun a rod, I shouldn't have good oil pressure.
If I had over-revved the engine, and had valves collide with pistons, the car shouldn't run.
Any other thoughts? The car's at a trusted garage, but I'm curious to what others think.
Worst case -- time for a modded motor.
Rob
Bad news is you can spin a rod/or main bearing and the oil pressure can remain the same. Good news is you may have roached a pulley, the AC compresser, power steering etc.
So as already suggested pull the belt and start the sucker.
